77 research outputs found

    Design of F-16 Airfoil Mock-ups for Supersonic Wind Tunnel: Study, Production, Testing and Validation

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    This research paper presents a comprehensive investigation into the behavior of viscous supersonic laminar flow and the Shock Wave- Laminar Boundary Layer Interaction (SWBLI) around the F-16 laminar NACA 6-series airfoil NACA 64A204. The study aims to establish and compare different methods for accurately describing these complex phenomena, which are of significant importance in the development of advanced aerospace technologies. To achieve this objective, a unique approach was adopted, involving the design and production of a mock-up F-16 airfoil equipped with pressure taps for use in the supersonic burst wind tunnel AF300. The mock-up was then experimentally tested, and the obtained data were analysed using numerical simulations with Ansys Fluent and a theoretical model based on a previously established analytical SWBLI model. The results obtained from the experimental, numerical, and analytical analyses validate the designed NACA 64A204 mock-up to a great extent. The study provides valuable insights into the physics of viscous supersonic laminar flow and SWBLI, contributing to a better understanding of these phenomena. The findings of this study will have important applications in the design of high-speed aircraft and other advanced aerospace technologies.Comment: 14 pages, 17 figures, 5 tables, submitted to Jounral of Applied Fluid Mechanic

    Micro-RNA content of circulating extracellular vesicles in early rheumatoid arthritis as biomarkers and mediators of methotrexate efficacy

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    Objectives Extracellular vesicles (EVs) are abundant in body fluids, contributing to intercellular signalling by transferring cargo that includes microRNAs (miRs)—themselves implicated in pathobiology. For the first time we evaluated the potential of EV miRs to contribute diagnostic information in early RA, predict methotrexate (MTX) efficacy or shed light on the drug’s mechanism of action. Methods Seven hundred and ninety-eight miRs isolated from serum-derived EVs of 46 patients with untreated RA, 23 with untreated polymyalgia rheumatica (PMR; inflammatory disease control group) and 12 in whom significant inflammatory disease had been excluded (non-inflammatory controls; NICs) were profiled (NanoString); the same measurements were made for RA patients after 6 months’ MTX treatment. Analyses took multiple testing into account. Results Twenty-eight EV miRs were robustly differentially expressed between early RA (but not PMR) patients and NICs after correction for age and sex, suggesting discriminatory value. Cross-validated partial least squares-discriminant analysis also indicated the predictive potential of a distinct baseline EV miR signature with respect to MTX-induced remission at 6 months. The change in expression of 13 miRs over the course of MTX treatment differed significantly between responders and non-responders, and four of those exhibiting increased relative abundance amongst responders have known roles in regulating the pathogenic potential of synovial fibroblasts, namely miR-212-3p, miR-338-5p, miR-410-3p and miR-537. Conclusion Our data highlight the potential of serum EV miRs as diagnostic and therapeutic biomarkers, highlighting a novel potential mechanism by which MTX may exert its therapeutic effect in early RA that warrants further investigation

    Interferon-α-mediated therapeutic resistance in early rheumatoid arthritis implicates epigenetic reprogramming

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    International audienceObjectives An interferon (IFN) gene signature (IGS) is present in approximately 50% of early, treatment naive rheumatoid arthritis (eRA) patients where it has been shown to negatively impact initial response to treatment. We wished to validate this effect and explore potential mechanisms of action.Methods In a multicentre inception cohort of eRA patients (n=191), we examined the whole blood IGS ( MxA, IFI44L, OAS1, IFI6, ISG15 ) with reference to circulating IFN proteins, clinical outcomes and epigenetic influences on circulating CD19+ B and CD4+ T lymphocytes.Results We reproduced our previous findings demonstrating a raised baseline IGS. We additionally showed, for the first time, that the IGS in eRA reflects circulating IFN-α protein. Paired longitudinal analysis demonstrated a significant reduction between baseline and 6-month IGS and IFN-α levels (p<0.0001 for both). Despite this fall, a raised baseline IGS predicted worse 6-month clinical outcomes such as increased disease activity score (DAS-28, p=0.025) and lower likelihood of a good EULAR clinical response (p=0.034), which was independent of other conventional predictors of disease activity and clinical response. Molecular analysis of CD4+ T cells and CD19+ B cells demonstrated differentially methylated CPG sites and dysregulated expression of disease relevant genes, including PARP9, STAT1, and EPSTI1 , associated with baseline IGS/IFNα levels. Differentially methylated CPG sites implicated altered transcription factor binding in B cells (GATA3, ETSI, NFATC2, EZH2) and T cells (p300, HIF1α).Conclusions Our data suggest that, in eRA, IFN-α can cause a sustained, epigenetically mediated, pathogenic increase in lymphocyte activation and proliferation, and that the IGS is, therefore, a robust prognostic biomarker. Its persistent harmful effects provide a rationale for the initial therapeutic targeting of IFN-α in selected patients with eRA

    Electro-thermal coupled battery model : State of charge, core and surface temperatures estimation

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    International audienceSince their emergence, lithium-ion batteries have played a major role in the growing market of electric vehicles thanks to their characteristics in term of power and energy density. However, the battery expected lifetime is still under investigation since it is influenced by State of charge, temperature and current rates. Which makes battery states prediction and thermal management essential to improve the Li-ion battery performance. Combining a three-state equivalent circuit model and a two-state thermal model, this paper proposes a coupled electro-thermal battery model capturing the State of Charge (SOC), the battery surface and core temperatures. Aiming to control the battery usage and avoid heating, the model is expressed in a state space form in order to allow state estimation and then SOC and thermal effects prediction. A simple state observer and a Robust Non Linear state estimator for SOC estimation are presented and compared. Then a nonlinear observer design for core and surface temperature is modeled, and the results obtained are discussed

    Electro-thermal coupled battery model : State of charge, core and surface temperatures estimation

    No full text
    International audienceSince their emergence, lithium-ion batteries have played a major role in the growing market of electric vehicles thanks to their characteristics in term of power and energy density. However, the battery expected lifetime is still under investigation since it is influenced by State of charge, temperature and current rates. Which makes battery states prediction and thermal management essential to improve the Li-ion battery performance. Combining a three-state equivalent circuit model and a two-state thermal model, this paper proposes a coupled electro-thermal battery model capturing the State of Charge (SOC), the battery surface and core temperatures. Aiming to control the battery usage and avoid heating, the model is expressed in a state space form in order to allow state estimation and then SOC and thermal effects prediction. A simple state observer and a Robust Non Linear state estimator for SOC estimation are presented and compared. Then a nonlinear observer design for core and surface temperature is modeled, and the results obtained are discussed

    Nushus Al–Waridah Fil Miqdar Al–Muharram Minarridha': Dirasah Tahliliah

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    This study explaines about views of Muslim jurists on the amount of breast milk that establishes fosterage and prohibits marriage based on the differences in the relevant legal texts. This research, critically, examines those texts, especially those that require five counts of breastfeeding. The methodology is based on critical examination of all the texts to establish their authenticity and relevance. The Researcher argued For safety, it is recommended to consider any amount of breastfeeding as a cause of fostering and prohibition. It concluded that there is doubt about the authenticity of those texts require five counts of breastfeeding
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